A strictly aerobic, non-spore-forming, Gram-negative bacterium, designated strain HW7T, was isolated from a rice field in Korea. Cells of strain HW7T were short rod-shaped and motile with single polar flagella. The major cellular fatty acids of strain HW7T were C16:o and summed feature 3 (C16:ω7c and/or iso-C15:0 2-OH). The genomic DNA G+ C content was 56 mol% and the major isoprenoid quinone was Q-8. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain HW7T forms a distinct lineage with respect to closely related genera within the class Betaproteobacteria and that the levels of 16S rRNA gene sequence similarity with respect to the type species of related genera are less than 93%. On the basis of the physiological and phylogenetic data, strain HW7T represents a novel genus and species of the Betaproteobacteria, for which the name Leeia: oryzae gen. nov., sp. nov. is proposed. The type strain is HW7T (= KCTC 12585T = DSM 17879T.